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The Single UNIX &reg; Specification, Version 2<br>
Copyright &copy; 1997 The Open Group

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<h4><a name = "tag_000_007_1027">&nbsp;</a>NAME</h4><blockquote>
pthread_atfork - register fork handlers
</blockquote><h4><a name = "tag_000_007_1028">&nbsp;</a>SYNOPSIS</h4><blockquote>
<pre><code>

#include &lt;<a href="systypes.h.html">sys/types.h</a>&gt;
#include &lt;<a href="unistd.h.html">unistd.h</a>&gt;

int pthread_atfork(void (*<i>prepare</i>)(void), void (*<i>parent</i>)(void),
    void (*<i>child</i>)(void));
</code>
</pre>
</blockquote><h4><a name = "tag_000_007_1029">&nbsp;</a>DESCRIPTION</h4><blockquote>
The
<i>pthread_atfork()</i>
function declares fork handlers
to be called before and after
<i><a href="fork.html">fork()</a></i>,
in the context of the thread that called
<i><a href="fork.html">fork()</a></i>.
The
<i>prepare</i>
fork handler is called before
<i><a href="fork.html">fork()</a></i>
processing commences.
The
<i>parent</i>
fork handle is called after
<i><a href="fork.html">fork()</a></i>
processing completes in the parent process.
The
<i>child</i>
fork handler is called after
<i><a href="fork.html">fork()</a></i>
processing completes in the child process.
If no handling is desired at one or more of these three points,
the corresponding fork handler
address(es) may be set to NULL.
<p>
The order of calls to
<i>pthread_atfork()</i>
is significant.
The
<i>parent</i>
and
<i>child</i>
fork handlers are called in the order
in which they were established by calls to
<i>pthread_atfork()</i>.
The
<i>prepare</i>
fork handlers are called in the opposite order.
</blockquote><h4><a name = "tag_000_007_1030">&nbsp;</a>RETURN VALUE</h4><blockquote>
Upon successful completion,
<i>pthread_atfork()</i>
returns a value of zero.
Otherwise, an error number is returned to indicate the error.
</blockquote><h4><a name = "tag_000_007_1031">&nbsp;</a>ERRORS</h4><blockquote>
The 
<i>pthread_atfork()</i>
function will fail if:
<dl compact>

<dt>[ENOMEM]<dd>
Insufficient table space exists to record the
fork handler addresses.

</dl>
<p>
The 
<i>pthread_atfork()</i>
function will not return an error code of [EINTR].
</blockquote><h4><a name = "tag_000_007_1032">&nbsp;</a>EXAMPLES</h4><blockquote>
None.
</blockquote><h4><a name = "tag_000_007_1033">&nbsp;</a>APPLICATION USAGE</h4><blockquote>
None.
</blockquote><h4><a name = "tag_000_007_1034">&nbsp;</a>FUTURE DIRECTIONS</h4><blockquote>
None.
</blockquote><h4><a name = "tag_000_007_1035">&nbsp;</a>SEE ALSO</h4><blockquote>
<i><a href="atexit.html">atexit()</a></i>,
<i><a href="fork.html">fork()</a></i>,
<i><a href="systypes.h.html">&lt;sys/types.h&gt;</a></i>
</blockquote><h4>DERIVATION</h4><blockquote>
Derived from the POSIX Threads Extension (1003.1c-1995) including PASC 1003.1c-95.
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UNIX &reg; is a registered Trademark of The Open Group.<br>
Copyright &copy; 1997 The Open Group
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